In the event of a secondary-side component short, some SMPS power supplies may shut down automatically even if they do not use a PWM IC. The printer's power source is a great illustration of this. Commonly, a printer's power supply board and main board hv power supply are separated by a cable. When there is a short circuit on the main board, the power supply won't work. Connector removal from the power supply board is required for fault isolation.
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